Back to EveryPatent.com
United States Patent | 5,601,338 |
Wahls | February 11, 1997 |
A seat particularly suitable for industrial applications having a hinged bottom supported upon springs for adjustably resiliently supporting the occupant to absorb vibrations and impact. The springs impose a resilient biasing force upon the seat bottom structure and a conveniently located adjusting knob selectively positions the location of the application of the biasing force with respect to the seat bottom hinge. Accordingly, by adjusting the location of application of the biasing force, the suspension characteristics of the seat bottom may be controlled and preselected with minimum manual exertion and no spring pre-tensioning or pre-compression is required to vary the suspension characteristics.
Inventors: | Wahls; Robert J. (Pinckney, MI) |
Assignee: | Michigan Seat Company (Jackson, MI) |
Appl. No.: | 408942 |
Filed: | March 23, 1995 |
Current U.S. Class: | 297/313; 116/285; 116/303; 297/284.11; 297/320; 297/332; 297/339; 297/452.55; 297/463.1 |
Intern'l Class: | A47C 003/32 |
Field of Search: | 297/284.1,284.2,313,284.11,339,452.18,452.23,452.55,452.57,463.1,463.2,320,332 116/285,284,303 |
974769 | Nov., 1910 | Hoff | 297/332. |
1025915 | May., 1912 | Hoff | 297/332. |
2395730 | Feb., 1946 | Farkas | 243/54. |
2531572 | Nov., 1950 | Knoedler | 155/9. |
2840140 | Jun., 1958 | Harrington | 155/51. |
3178221 | Apr., 1965 | Schwarz | 297/284. |
3301520 | Jan., 1967 | Barth et al. | 297/333. |
3743230 | Jul., 1973 | Freedman | 248/399. |
4640488 | Feb., 1987 | Sakamoto | 248/588. |
4687250 | Aug., 1987 | Esche | 297/320. |
4712834 | Dec., 1987 | Warrick | 297/284. |
4781417 | Nov., 1988 | Shipman et al. | 297/452. |
4890887 | Jan., 1990 | Koutsky et al. | 297/320. |